The cylindrical or conch shaped building was built in 1649 C.E. by the first Governor of Paro, LangonpaTendzinDrugpa, thehalf brother of the Zhabdrung. It served as a watchtower to protect the Paro Rinpung Dzong below from invasions from all directions. The architecture of the building is unusual in that not only does the building resemble a conch shape with an internal spiral, but the building design also reflects the union of the sun (circular shape) and the moon (crescent shape) which can be seen from the outside. This union symbolises fame and victory reflected in all directions.
At the time, the dzong was the center of both the administration of the state as well as the location of the monastic and spiritual life of the valley The unique structure of the watchtower, or Ta-Dzong, has six floors that spiral down from the top. Its stone walls are two and half meters thick. When it was functioning as a watch tower, the building not only housed soldiers but also prisoners of war.
By the end of the 1950s, the watchtower had reached a state of near collapse.The Third King, Jigme Dorji Wangchuck, proposed that it be renovated and converted into a museum. The Bhutanese government renovated the entire structure and provided the necessary infrastructure to house and display the national collections. The Museum was opened to the public in 1968.
Current facilities of the Museum include the main building, the Ta-Dzong, which has six floors of exhibits.The Museum also has secondary exhibition space in a modern building behind and uphill from the main building.On the ground floor there is flexible gallery space for visiting and rotating exhibits